Specify your system name, version and architecture, it is very good idea to include the name of your OS in the topic title, for example: Windows XP: Game is crashing when...

Be verbose, post backtrace, strace, content of tmw.log, versions of dependent software etc. Make sure all of depencies are installed and has correct versions.
See: http://wiki.themanaworld.org/Dependencies
Do not use pastebins because content pasted there expires.

Respect the time of developers and helpers - use descriptive topic titles, subjects like "OMFG game isn't working", "WTF HELP!", "GOT PROBLEM!" are not acceptable, and usually indicates that the author is a person not to be treated seriously. Good topic title is eg.: Linux: Can't load map file - unknown error.